Physical Therapy Assistant Practice Exam

Which muscle is involved in activities requiring scapula retraction?

1. Rhomboids

2. Latissimus dorsi

3. Trapezius

4. Deltoid

The correct answer is: Rhomboids

The rhomboids are primarily responsible for scapula retraction, which involves pulling the shoulder blades toward the spine. This muscle group consists of the rhomboid major and rhomboid minor, both of which are located between the spine and the scapula. When these muscles contract, they draw the scapulae medially, stabilizing the shoulder girdle and enhancing posture as well as functional movements like rowing and pulling. The latissimus dorsi, while involved in various shoulder movements, primarily functions to extend and adduct the arm rather than directly retracting the scapula. The trapezius does assist in scapula retraction, but it also has multiple functions including elevation and rotation of the scapula, making the rhomboids more specifically tied to this action. The deltoid, on the other hand, primarily focuses on arm abduction and does not play a direct role in scapular movement. Thus, the rhomboids stand out as the key muscles responsible for activities that require scapula retraction.